Читать книгу Continuous Emission Monitoring - James A. Jahnke - Страница 41

The Cross‐State Air Pollution Rule, of 40 CFR 96, evolved from the Clean Air Interstate Rule (CAIR) and the NO_x Budget Program (NBP). After the promulgation of Part 75 and the implementation of the acid rain program, significant progress was made in reducing SO₂ and NO_x emissions. However, even with 50% reductions in SO₂ and NO_x emissions, critical load was not being reached. “Critical load” is the level of emissions below which harmful effects to the environment do not occur. Studies indicated that reductions on the order of 75% on top of the previous 50% reductions would be necessary for SO₂ and NO_x to meet ambient air standards for ozone and particulate matter, as well as reaching critical load requirements for acid rain. In the East, it was felt that part of the problem was due to the interstate transport of pollutants from the western to eastern parts of the United States. Thus, began the saga of rulemaking that extended from the NO_x Budget Trading Program, to the Clean air Interstate Rule, and to the Cross‐State Air Pollution Rule, which is in effect today.